The present invention relates to a knitted fabric which has a look and feel similar to woven fabrics and to apparatus and methods of making such fabric. Particularly, the present invention relates to weft inserted, warp knit woven-appearing fabric having aesthetic and structural characteristics similar to those of conventional woven fabric and to apparatus and methods of making such fabric.
Efforts have previously been made to produce fabric which has the aesthetics, dimensional stability, drapability and other characteristics of woven fabric but which may be produced with the production speed and other advantages of knitting, for example, by warp knit weft insertion machines. As well known, woven fabrics have dominated the marketplace because of their very desirable characteristics including their stability and capacity to be made in an almost limitless variety of patterns. Warp knit, weft insertion machinery, however, has the ability to increase the speed of production of a fabric, as well as to use inferior yarn, in some cases, as compared to even the fastest of weaving machines. Warp knit, weft insertion fabric is also quite stable. However, the advantages afforded by its higher fabric production speed are offset to some extent by the increase in yarn usage necessary to produce textures, patterns or depth of fabrics similar to those characteristics in woven fabrics.
In order to provide a woven look-alike fabric by a warp knit, weft insertion technique, a fabric construction is necessary which affords the impression and aesthetics of being woven. This usually requires more yarn and is therefore more costly. Also, its effect is seldom satisfying. That is, it is usually sufficiently different from a woven fabric construction as to be deficient in certain desired characteristics, i.e., structural stability, the ability to create a variety of patterns, capacity for utilizing different yarns, etc.
One effort to provide a knit fabric having a woven appearance is described in U.S. Pat. No. 3,952,550. In this patent, an objective is to provide a fabric which has a woven appearance from both sides of the fabric. In this fabric, the warp-weft configuration is interlaced with the stitching construction. That is, a stitching construction is incorporated with the warp-weft configuration in order to hide the stitch loops or underlaps to the extent possible, thereby to enhance the woven-like features of the knitted fabric. More particularly, the fabric construction of this patent is such that the first weft is held between the loop portion and underlap portion of the stitch, as well as under the warp yarn between stitch wales. The second weft within the stitch is on top of the underlap portion of the stitch and under the warp yarn between stitch rows. In this manner, the stitching forms part of the interlacing of the warp and weft. The construction of the fabric disclosed in this patent is also limited to at least two wefts within a course. The knitted fabric of this patent, moreover, cannot avoid a large number of relatively closely spaced stitch wales in order to incorporate the stitching construction with the warp and weft construction to provide the woven appearing fabric. This, however, substantially increases costs as the greater the number of stitches, the greater the expense of producing the fabric. Moreover, the apparatus necessary to make the knit fabric of that patent is highly complex, limiting the weft yarns and weft repeats to one or two different kinds, thereby limiting the texture and color of yarns employable with the apparatus. It also renders it extremely difficult to provide fabrics in different patterns, such as checks, tight or open areas in the cloth, etc.
In accordance with the present invention, a warp knit, weft inserted, fabric may be formed to provide a woven appearance in relation to the warp and weft between stitch wales but which does not use the stitch wales themselves as part of the woven look-alike interlacing of the warp and weft. That is, the present invention provides a warp knit, weft inserted, woven look-alike fabric wherein the warp-weft configuration is independent of and does not include the stitching construction in the warp-weft interlacing scheme. It is also possible in accordance with the present invention to lay a weft yarn over a warp yarn and under one or more adjacent warp yarns in the same course by providing two or more each of weft carriers and warp beams. Consequently, in the present construction, one or more weft yarns are laid by a weft carrier, for example, between chains on opposite sides of the fabric and which chains transport the yarn in the warp direction. Downstream of the first weft carrier, there is provided one or more warp yarns laid on top of the first layer of wefts, thus, locating the first wefts below the first warps. Further downstream, a second weft carrier lays one or more additional wefts on top of the first warps and further downstream, yet another one or more warp yarns are laid on top of the second weft yarns. Preferably, but not necessarily, the second weft yarns are laid alternately between the first weft yarns and similarly the second warp yarns ar laid, preferably alternately, between the first warp yarns. Preferably, none of the weft yarns register with one another. It will be appreciated that the sequence may be continued with third and additional weft and warp yarns being laid in this interlaced pattern to fill the fabric.
With this technique of interlacing warp and weft, it will also be appreciated that warp ends could be laid between the wales of stitches without covering the entirety of the weft. This would simulate a more dense fabric than the gauge of the machine would indicate. By using a relatively coarse gauge machine for a visually denser fabric, the quantity of stitching yarn would be reduced. Further, multiple warp ends placed between stitches tend to touch one another in warp knitting, requiring the use of more ends per unit for a particular density than in weaving, where they are slightly separated through the interlacing of warp and weft. By the slight separation of two adjacent warp ends placed between two adjacent stitching wales, yarn consumption for a given density or opacity of fabric is minimized. Similarly, use of doubled wefts lying within a course minimizes yarn usage.
The fabric formation is accomplished in accordance with the present invention such that the stitches are independent of the interlaced warp and weft. In such stitching, the first weft within one course is held between the loop portion of the stitch and the stitch underlap. As seen from the technical front of the fabric, warp yarn between the stitch wales lies under the weft. The next weft or multiples thereof in the second group of weft yarns within the next course are again located between the loop portion of the stitch and the stitch underlap. The warp yarn of the previously mentioned warp between the stitch wales, however, is now over that weft.
It will also be appreciated that one or more substrates may be incorporated into the woven-appearing fabric. The substrate is stitched to the fabric and may comprise non-woven, woven, knitted or netted material which may be substituted for any one of the laid-in weft yarn sets or on either side of the fabric.
In a preferred embodiment according to the present invention, there is provided a warp knit, weft inserted, fabric having a woven-like appearance, comprising plural stitch wales having a plurality of substantially parallel courses with the stitch in each wale at each course having a technical face side segment and a technical back side segment, a first set of weft yarns, each of which is held in the fabric by the technical back side segment, a second set of weft yarns, each of which is held in the fabric by the technical face side segment, and plural warp yarns disposed between the first and second sets of weft yarns and extending in the warp direction between predetermined adjacent stitch wales. Preferably, the stitches are chain stitches so that the technical face side segments are the loop portions of the stitches and the technical back side segments are the underlap portions of the stitches. In a further preferred embodiment, the first and second sets of weft yarns may be disposed in alternating courses, or certain courses may have no wefts therein.
In a still further preferred embodiment according to the present invention, there is provided a warp knit, weft inserted, fabric having a woven-like appearance, comprising plural stitch wales having a plurality of substantially parallel courses with the stitch in each wale at each course having a loop portion and an underlap, a first set of weft yarns each being respectively inserted in those of the chain stitches which establish selected ones of the courses such that predetermined adjacent ones of the first weft yarns are spaced one from the other in the warp direction by others of the chain stitches which establish at least one intermediate course between the selected ones of the courses in which the predetermined adjacent ones of the first weft yarns are inserted. A second set of weft yarns are each inserted in a respective at least one intermediate course. Each of the at least one intermediate course receives a weft yarn of the second set lying next adjacent one of the selected ones of the courses receiving a weft yarn of the first set with the weft yarns of the next adjacent courses bound to the fabric by the underlap of the stitches. Plural warp yarns are disposed between the first and second sets of weft yarns and extend in the warp direction between predetermined adjacent stitch wales. If desired, yarns of the first and second sets could be inserted in the same course instead of or, in addition to, alternating courses. Further, the courses with first and second sets need not be alternating, but other patterns may be used.
In a still further preferred embodiment according to the present invention, there is provided a warp knit weft inserted fabric having a laid-in warp and a relatively open woven appearance comprising a first layer of spaced-apart laid-in weft yarns, a second layer of laid-in spaced apart warp yarns and a third layer of laid-in spaced-apart weft yarns, wherein the weft yarns of the third layer are not in registration with the weft yarns of the first layer, the first, second and third layers being held together by relatively fine warp stitching yarns such that the yarns of the three layers have an interlaced woven-like appearance.
In a still further preferred embodiment according to the present invention, there is provided a method of forming a warp knit, weft inserted, fabric having woven-like appearance comprising the steps of providing plural stitch wales having a plurality of substantially parallel courses with the stitch in each wale at each course having a technical face side segment and a technical back side segment, providing the fabric with first and second sets of weft yarns, disposing plural warp yarns between the first and second sets of weft yarns and extending in the warp direction between stitch wales and holding both the first and second sets of weft yarns in the fabric by the technical back side or technical face side segments of predetermined ones of the stitches.
In a still further preferred embodiment according to the present invention, there is provided a method of forming a woven-like appearing fabric by a warp knitting, weft insertion process having plural stitch wales and courses extending in the respective warp and weft directions, comprising the steps of extending a first weft yarn set in a weft direction to establish selected ones of stitch courses such that predetermined adjacent ones of the first weft yarns are spaced one from the other in the warp direction by others of the stitch courses to establish at least one intermediate course between the selected ones of said courses, extending a first warp yarn set past the first weft yarn set, extending a second weft yarn set in the weft direction past the first warp yarn in the one intermediate course and on the side thereof opposite the first weft yarn set, forming a plurality of stitch wales between predetermined warp yarns to establish a plurality of substantially parallel courses, with the stitch in each wale at each course having a loop portion and an underlap portion. There is also provided the step of forming the stitch wales, including binding the weft yarns of each next adjacent course by the underlap of the stitches to interlace the sets of weft and warp yarns and provide a woven-like appearance.
In a still further preferred embodiment according to the present invention, there is provided apparatus for manufacturing a warp knit, weft inserted, fabric having a woven-like appearance, comprising a frame, knitting means carried by the frame and means carried by the frame for conveying weft yarns in a predetermined direction. A plurality of carriages are mounted for movement in a direction transverse to the predetermined direction for laying first and second sets of weft yarns on and between the conveying means. Also provided are means for laying warp yarns in said predetermined direction between the first and second sets of weft yarns. The knitting means for forms a plurality of stitches in plural stitch wales disposed between the warp yarns in plural, substantially parallel, courses of stitches, with the weft yarns secured in the fabric by the stitches.
In a still further preferred embodiment according to the present invention, there is provided a method of manufacturing a warp knit, weft inserted, fabric having a woven-like appearance, comprising the steps of disposing first and second sets of weft yarns sequentially on a conveyor for movement toward a knitting area, laying warp yarns on the conveyor between the first and second sets of weft yarns by laying the warp yarn on the first set of weft yarns on the conveyor and laying the second set of weft yarns upon the warp yarns, forming a plurality of stitches in plural stitch wales disposed between the warp yarns and in plural, substantially parallel courses thereof and securing the weft yarns in the fabric by the stitches.
Accordingly, it is a primary object of the present invention to provide a novel and improved weft insert warp knit woven-look fabric and apparatus and methods of making the fabric and particularly characterized by a woven look wherein the stitches are not a part of the interlaced warp and weft, but may contribute to the woven look.
These and further objects and advantages of the present invention will become more apparent upon reference to the following specification, appended claims and drawings.